The Greubel Forsey double balancer 35° has two inclined fixed balance wheels, a real first in the watch industry.
This unique adjustment system includes two tilted oscillators and escapement. They are driven by a spherical differential that provides an average value of their speed to the time display through a gear train.
Basic research since 1999, when Robert Greubel and Stephen Forsey began their pioneering research on tilted oscillators, they first focused on the huge challenges of installing in a rotating cage, and then continued to study tilted fixed oscillations in the early 21st century Device.
The first working prototype of Greubel Forsey‘s sixth basic invention was the sixth basic invention with a tilt escapement. It was originally a movement with two tilt oscillators, each tilted at 20°, and It was unveiled at the Basel International Watch and Jewellery Fair in 2009. This concept of superposition led to the 2011 label of the exclusive six-timer version under the Goppelfort EWT. Therefore, the timepiece shown today is evolved from the first concept. The two inclined oscillators no longer overlap, but are spatially distributed in different three-dimensional planes.
Derived from years of basic research on the tilt of the oscillator and escapement, the dual balancer 35° provides an important way to improve the chronograph performance of the watch, both on and off the wrist.
A movement with two oscillators tilted on different three-dimensional planes provides two significant factors in the pursuit of better timekeeping performance.
First, the tilt oscillator works in a stable position to significantly reduce the possibility of being in a horizontal (flat) or vertical position. The second is that the two tilted fixed oscillators are connected by a spherical differential, averaging the rated difference and ensuring the best performance is always in a stable (horizontal or vertical) position or dynamic (on the wrist). The chronograph result of the first place in the 2011 International Timing Competition with the 30° dual tourbillon technology of Gaupe Fortunes confirms Gaupe Fortunes’ basic research on oscillators that work on slopes.
The iconic Goperfuss skeletonized gold hands with high-definition Super-LumiNova tip indicate the time and polished black oxidized gold chapter ring between the two visible tilting balance wheels at 35° of the double balancer, and the small seconds at 7 o’clock shows the movement The instantaneous average of the two regulators, and the 72-hour power reserve indicator at 2 o’clock tracks the best power provided by the two coaxial, rapidly rotating main barrels. The 35° angle of inclination of the tilted balance wheel allows a larger diameter balance wheel (better inertia for more stable timing) to be installed in a very comfortable 43.5 mm case.
Greubel Forsey Double Balancier 35° is a one-off unique version, made of 18k white gold, which is unique.
Finishing and aesthetics
Like all Greubel Forsey timepieces, the Double Balancier 35° is hand-finished and decorated without compromise. The design of the movement components maximizes their beauty, providing countless noble details that are discoverable and respectable. The frosted board, black flat polished steel and stunning hand-polished bevels with sharp inner corners (which machines cannot do like experienced hands) bring unparalleled vitality. The large jewels and mirror-polished screws embedded in the polished gold casing prove that all aspects of this timepiece are of high quality.
Technical data complete
The manual winding movement consists of 365 parts, 28 of which constitute a spherical differential. It is powered by two concentric, fast-rotating main barrels, which can provide the best power for 72 hours. The two oscillators are equipped with variable inertia balance wheels, Phillips terminal curve and 3Hz/21,600 APH. Plates and bridges are made of nickel silver, frosted and spotted, polished bevels and countersinks, straight-grained sides and anthracite treatment (NAC).
The case is made of 18k white gold, with a diameter of 43.5 mm and a height of 14.35 mm. The dial side and the back of the display are equipped with synthetic sapphire crystals. Three-dimensional, variable geometry lugs, screw fixation, polished engraving “Double Balancier 35°” raised on a hand-punched background, gold safety screws, two hand-engraved platinum plates fixed with screws to the case, and one Hand-carved personal figures. The black alligator leather strap features a hand-stitched white gold folding clasp.